Clip arrangement for dental film processing hangers

ABSTRACT

A clip arrangement for dental film processing hangers comprising a fixed jaw carried by the hanger and defining a generally planar gripping portion including a spherically contoured button and a pair of coplanar stop surfaces on either side of same, with the button defining at its mid portion a rounded opening having a burr thereabout that is substantially in the plane of said stop surfaces, and a spring biased movable jaw pivoted to the fixed jaw and including a tang formed with a blunt gripping end and a pair of tab portions on either side thereof. In the closed position of the clip in gripping a film, the movable jaw tabs grip the film at the respective stop surfaces, and the tang is centered on the opening but is stopped from movement into same to bias the film into engagement with the burr without dimpling it, whereby a secure three point holding action is applied to the film.

United States Patent Rinn et al.

[ CLIP ARRANGEMENT FOR DENTAL FILM PROCESSING HANGERS [72] Inventors: Irwin C. Rinn, Sleepy Hollow;

Charles F. Stevenson, Elgin, both of Ill.

[73] Assignee: Rinn Corporation [22] Filed: July 26,1971

.[21] Appl. No.: 165,930

Primary Examiner-Samuel S. Matthews Assistant Examiner-Richard M. Sheer 451 Aug. 15, 1972 Att0rney-Robert C. Brown, Jr. et al 5 7 1 ABSTRACT A clip arrangement for dental film processing hangers comprising a fixed jaw carried by the hanger and defining a generally planar gripping portion including a spherically contoured button and a pair of coplanar stop surfaces on either side of same, with the button defining at its mid portion a rounded opening having a burr thereabout thatis substantially in the plane of said stop surfaces, and a spring biased movable jaw pivoted to the fixed jaw and including a tang formed with a blunt gripping end and a pair of tab portions on either side thereof. In the closed position of the clip in gripping a film, the movable jaw tabs grip the film at the respective stop surfaces, and the tang is centered on the opening but is stopped from movement into same to bias the film into engagement with the burr without dimpling it, whereby a secure three point holding action is applied to the film.

' 7 Claims, 6 Drawing Figures PATENTEDAU: 15 1912 SHEET 2 BF 2 II"- n CLIP ARRANGEMENT FOR DENTAL FILM PROCESSING HANGERS This invention relates to a clip arrangement for dental film processing hangers, and more particularly, to the film gripping portions of the clip for the purpose of improving the hold of the clip on the film.

Dental film processing hangers conventionally comprise a hook having an elongate shank to which one or more pairs of film clips are attached in spaced apart relation along the length of the shank. Each pair of clips comprises a cross plate element fixed to the hanger shank and forming at each end thereof the fixed jaw of the pair of clips at that location on the hanger. Each fixed jaw pivotally mounts a spring biased movable jaw having a tang that clamps the film against a smooth surfaced rounded button formed on the fixed jaw cooperating therewith. The film is also clamped between spaced tabs on either side of the button cooperating with stop forming flanges formed on the fixed jaw on either side of the button.

Dental film for many years was made from an acetate base material that was relatively soft. The clip tang dug into the film when the film was applied to the clip and held it firmly against displacement during application and removal of the hangers to and from thedeveloping tank.

However, in recent years, the base of most dental film is polyester, which is of a tougher texture than acetate. It has been found that the movable jaw does not dig into the polyester base film, which prevents the clip from firmly holding the film, and the softening of the emulsion of the film base by the chemicals during processing aggrevates this condition.

The result is that the shaking of the water and chemicals off of the film that is necessary during processing readily dislodges the films from the clip. As a matter of fact, the polyester base film tend to fall ofi the hanger even without shaking, while hanging in the processing tank, with resulting inconvenience that is obvious.

A principal object of this invention is to significantly improve the holding action of the clip on the film without materially changing the general arrangement of the hanger.

Another principal object of the invention is to modify the manner in which the film is gripped by the clip so that the clip will hold both acetate and polyester base film with equal facility against displacement during all necessary handling that takes place during processing of the film.

Still other objects of the invention are to provide a dental film clip arrangement that is economical of manufacture, convenient in use, and long lived in operation.

In accordance with this invention, the clip button, which is defined by an indentation in the fixed jaw, is pierced from the back side of the jaw to define a rounded opening in the button encircled by a jagged edge or burr projecting in the direction of the movable jaw tang. The movable jaw' tang is formed with a blunt gripping end that in its gripping position is centered on the button opening but is slightly spaced above it a dimension somewhat less than the film. The film when gripped by the movable jaw is thus held against the burr 2 identification dimples conventionally formed in the film.

Yet other objects, uses and advantages will be obvious or become apparent from a consideration of the following detailed description and the application drawings.

In the drawings:

FIG. '1 is a plan view of a dental film processing hanger arranged in accordance with the present invention, with dental film shown in broken lines as they are applied to the respective clips in use in the hanger;

FIG. 2 is an elevational view of one of the pairs of clips applied to the hanger, taken substantially along line 2-2 of FIG. I, but with the film removed;

FIG. 3 is a fragmental cross-sectional view through the fixed jaw of one of the clips, taken substantially along line 3-3 of FIG. 1, illustrating an important improvement in the clip arrangement;

FIG. 4 is a longitudinal cross-sectional view through one of the clips, taken substantially along line 4-4 of FIG. 1, and on an enlarged scale, better illustrating the details of the clip and the manner of its operation;

FIG. 5 is a front elevational view of the clip shown in FIG. 4, taken substantially along line 5-5 of FIG. 4', and

FIG. 6 is a cross-sectional view taken substantially along line 6-6 of FIG. 4.

However, it is to be understood that the specific drawing illustrations provided are supplied primarily to comply with the requirements of the Patent Laws, and that the invention may have other embodiments that are intended to be covered by the appended claims.

GENERAL DESCRIPTION Reference numeral 10 of FIG. 1 generally indicates'a dental film processing hanger arranged in accordance with this invention comprising a hook member 11 including the usual hooked end 12 and shank 14 to which is applied one or more film clip devices 16. The film clip devices 16 are identical and the number applied to any one hanger 10 will depend on the size of the hanger desired.

Each clip device 16 comprises a rectilinear plate or bar element 18 suitably affixed to the hanger shank 14, as by spot welding at 20, and defining at either end of same a fixed or stationary jaw 22 of the respective film clips 24, which also include movable jaw 26.

Each clip 24 is of identical construction and the description of one clip 24 will apply to all.

The fixed jaw 22 of each clip defines a substantially planar gripping area 28 that includes a centrally located button or protuberance 30 of generally spherically contoured rounded shape. On either side of the button 30 the fixed jaw 22 defines stop surfaces 32 that are engaged by spaced tabs 34 defined by the movable jaw 24.

The movable jaw 26 includes gripping end 36 formed to define a tang 38 that is intended to engage the film 40 intended to be gripped by the respective clips 24, and a handle or finger engaging end 42 for the purpose of swinging the tang 38 upwardly or away from the fixed jaw 22 for application thereto or removal therefrom of a film 40. Movable jaw 26 is biased into engagement with the film 40, in the embodiment illustrated, by suitable U-shaped leaf spring 44 (see FIG. 4)

to which movable jaw 26 and fixed jaw 22 are connected to swingably or pivotally mount the movable jaw 26 relative to the fixed jaw. Pivotal movement of the movable jaw 26 is limited by stop surfaces 32 and catch arrangement 46 (see FIGS. 4 and 6).

In accordance with this invention, the button 30 is pierced from the underside 50 thereof to form rounded opening 52 about the mid portion of the button 30, thereby defining a jagged edge 54 thereabout in the form of a circumambient burr 56 that projects upwardly of the button in the general direction of the movable jaw 26 and into the plane that the film 40 occupies when applied between the fixed and movable jaws for gripping purposes (see FIGS. 4 and The gripping end portion 60 of movable jaw 26 is flattened or blunted in'the manner indicated to avoid piercing the film. Furthermore, the fixed and movable jaws 22 and 26 are arranged so that the end portion 60 of tang 38, in gripping a film under the action of spring 44, does not lodge in the button opening 52 in the closed position of the movable jaw, but rather is centered above same a suitable dimension that is less than the thickness of film to be handled by clips 24 (see FIGS. 4 and 5).

In use, a film 40 is applied to a clip 24 by depressing the handle end portion 42 of the movable jaw 26 downwardly to substantially the position indicated by the broken line showing of FIG. 4, and then inserting the edge 62 of the film between the fixed and movable jaws, with the film being moved across the button 30 of the fixed jaw 22 and under the tabs 34 of the movable jaw 24. On release of the movable jaw end portion 42, spring 44 biases the jaw 26 counterclockwise of FIG. 4 to cause the movable jaw tabs 34 to press the film against the fixed jaw stop surfaces 32, and to cause the tang 38 to engage the film and press it against the burr 56 whereby a unique three position holding action is achieved on the film.

The end 60 of tang 38, which, as indicated, is not a sharp point, but which is flattened somewhat as indicated at 64, digs into the film without actually penetrating it or tending to form a permanent indentation in the film comparable to the familiar dimple that may be in the film for identifying purposes. The burr 56, the prongs 57 of which should not project more than about three thousandths of an inch above the top of button 30, provides a roughness on the button that increases the friction hold of the clip on the film sufficiently to avoid dislodgement of the film as a result of routine handling during processing. The showing of the burr prongs 57 in the drawings is greatly enlarged for illustrative purposes.

The film is released by depressing the movable jaw 26 at its end portion 42. The parts are arranged so that when the film 40 is not being gripped by a clip movable arm 26, on the jaw 26 moving to closed position, tabs 34 engage stop surfaces 32, disposing the flattened end edge 64 of tang 38 about the level of burr 56 in alignmentwith opening 52.

SPECIFIC DESCRIPTION The hanger element 11, the element 18 forming the fixed jaw 22, and the springs 44 are preferably formed from stainless steel or the like materials that resist the solutions in which they will be immersed without tarnishing.

The hanger element 11 may be of simple J-shaped configuration comparable to existing hangers used in this art.

The elements 18 in the form shown each comprise a channel shaped member defining a web 82 and side flanges 84 and 86, with the web 82 of the respective elements 18 being affixed to the shank 14 of hanger element 11 by spot welding as at 20. Elements 18 are preferably afiixed to the shank 14 substantially at right angles thereto.

The web 82 of member 80 at either end thereof defines the flattened gripping area 28 which is indented, in the form shown, as at 88 to define the button protuberance 30 having generally spherically contoured surface 90. Opening 52, which is located at substantially the mid portion of button 30, is preferably formed by a suitable punching action bursting through the material to leave the burr 56. It is pointed out that there is no intention to cut the metal of member 82 in forming the opening 52 as it is desired that the edge 54 be jagged in configuration and have jagged edging portions about the circumference of the opening 52, the projections 57 of which preferably should not be of greater length than about three thousandths of an inch.

Member 80 is also indented as at 92 to define protuberance 94 which seats within opening 96 of spring arm 98.

Adjacent either end of the members 80, the flanges 86 and 84 are enlarged as at 100 and 102, respectively, to form the catch devices 46 for limiting the movement of movable arms 24. For this purpose, the respective flanges 84 and 86 have opposing right angled tabs 104 and 106 formed in their respective portions 100 and 102 which are received in notched flanges 108 and 110 of the movable jaw in the manner indicated in FIGS. 4 and 6. Flanges 84 and 86 at the ends of the member 80 form the respective stop surfaces 32, the respective flange enlargements 100 and 102 terminating short of the surfaces 32 in upright edge surfaces 112 and 114 that are perpendicular to the respective surfaces 32. In applying a film 40 to a clip device of this invention, the film may be inserted between the open jaws until its edge 62 engages the respective edge surfaces 112 and 114, which thus serve a locating function in applying the film to the clip.

The movable jaw 26 comprises a lever member that'intermediate its ends is flanged .as at 108 and 110,

which flange portions 108 and 110 are each formed with a right angled slot 126 in which the respective tabs 104 and 106 are received in the manner indicated in FIGS. 4 and 6. The lever member 120 at the end 36 of the movable member 26 is given the generally triangular configuration that is indicated in FIG. 5 and suitably angled with respect to the remainder of the member 120 to provide the relationship of parts indicated in FIG. 4. As already indicated, the end of the tang 38 is flattened somewhat as at 64 to avoid providing a sharp point at the working end of tang 38.

Lever member 120 is also indented as at 130 to provide a protuberance 132 which seats within locating recess 134 of spring arm 136. Member 120 is also formed to define a perforation 138 to aid in draining of the process liquid from within the clip movable member on removal of the hanger from the processing tank.

Spring 44 is a leaf spring in the substantially U-form as indicated in FIG. 4, including spring arms 98 and 136 merging in bight portion 140. Protuberances 94 and 132 of the fixed and movable jaws seated in locating openings 96 and 134, respectively, retain the spring in operating position.

This results in the spring 44, which is designed to act as a compression spring, biasing the movable member 26 to move or rock counterclockwise of FIG. 4 with respect to the fixed jaw 22, and thus bias movable jaw tabs 34 and tang 38 toward stop surfaces 32 and button 30 of the fixed member, respectively.

In one successful embodiment of. the invention, the button or dimple 30 at its base 144 is 0.1 inch in outer diameter, opening 52 is 0.031 inch in diameter, with the prongs 57 of burr 56 not exceeding approximately 0.003 inch projection from the spherically contoured surface 90 of button 30. Tang edge 64 is 0.016 inch in length (in the plane of the tang) or roughly one half the diameter of opening 52.

Stop surfaces 32 are 0.41 inch apart transversely of the member 80, and opening 52 of button 30 is on a center spaced 0.0575 inch forwardly of the edge surfaces 112 and 114.

The depressing of the handle portion 42 of the movable jaw 26 toward the fixed jaw 22 of the clip 24 provides the basic pivotal or rocking action involved, the movable jaw tabs 104 and 106, on release, engaging edge surfaces 160 in the respective 126 at about the same time that tabs 34 engage the respective stop surfaces 32 under the biasing action of spring .44 to limit the movement of the gripping portions of the movable jaw 26 toward the corresponding portion of the fixed jaw 22. As indicated, in the closed position of jaw 26 (when holding a film under the action of spring 44), its blunt edge 64 is spaced from opening 52 while being substantially centered on same. This spacing should be less than the thinnest film to be handled by clips 24, for instance, the thinnest film currently marketed for dental film purposes is 0.007 in thickness and thus the spacing indicated should be somewhat less than that for devices intended to be for general use.

Spring 44 should be designed to provide the spring action necessary to effect the engagement of the tang with the film, relative to stop surfaces 32 and burr 56, that is indicated in FIG. 4.

The movable jaw blunt edge 64 avoids excessive penetration of the softer acetate films, thus permitting effective use of clips 24 on acetate film as well as the tougher polyester film. i

it will therefore be seen that there has been provided a simple but effective clip device that includes a special relationship of parts that permits the clip to effectively retain both acetate and polyester base film materials against displacement during normal handling procedures as film is being processed.

The foregoing description and the drawings are given merely to explain and illustrate the invention and the invention is not to be limited thereto, except insofar as the appended claims are so limited, since those skilled in the art who have the disclosure before them will be able to make modifications and variations therein without departing from the scope of the invention.

We claim:

1. In a film processing hanger including a film clip comprising a stationary jaw, and a movable jaw mounted for movement toward and away from the fixed jaw, and means for biasing the movable jaw toward the fixed jaw, the improvement wherein:

said fixed jaw includes a substantially flat gripping portion having a protuberance formed therein directed toward said movable jaw,

said protuberance at its mid portion being formed to define an opening therethrough having a burr formed thereabout and projecting toward said movable jaw,

said movable jaw defining a tang formed with a blunt gripping end and said tang being mounted relative to said fixed jaw such that in the closed position thereof said movable jaw tang end is substantially centered on and spaced from said protuberance opening,

whereby the film is pressed against said burr by said tang gripping end without said tang end penetrating the film.

2. In a film processing hanger including a film clip comprising a stationary jaw having a generally planar gripping end including a generally spherically contoured protuberance on one side surface thereof, a movable jaw opposing said stationary jaw and including a gripping end directed toward said protuberance, and means for biasing said movable jaw end toward said protuberance, the improvement wherein:

said protuberance at its mid portion is formed with a circular burr projecting substantially normally of said one surface and in the general direction of said movable jaw end,

said movable jaw being mounted to dispose said end thereof in substantial centered relation with said protuberance burr and spaced therefrom but less than the thickness of the film in the closed position thereof.

3. In a film processing hanger including a film clip comprising a fixed jaw having a gripping end portion defining a generally planar gripping section including a generally spherical protuberance on one side surface thereof, a movable jaw opposing said fixed jaw and including a gripping tang at one end thereof that is directed toward said protuberance, and a handle portion at the other end thereof, with said movable jaw being mounted for pivotal movement of said tang toward and away from said fixed jaw about an axis intermediate said ends thereof, and means for biasing said movable jaw tang toward said fixed jaw, the improvement wherein:

said protuberance at its mid portion is formed with a circular burr projecting substantially normally of said one surface and in the general direction of said movable jaw said one end, said movable jaw being mounted to dispose said tang thereof in substantial centered relation with said protuberance burr in the closed position thereof,

and stop means for spacing said tang from said protuberance but less than the thickness of the film in the closed position thereof,

said tang having a blunt gripping end portion that engages the film to press same against said protuberance burr in said closed position of said tang.

4. In a dental film processing hanger for holding both acetate and polyester dental film including a film clip for holding the film and comprising a fixed jaw secured to the hanger and defining a gripping end portion projecting from the hanger and terminating in a marginal edge, said fixed jaw end portion being formed to define a generally planar gripping section including a spherically contoured protuberance on one side surface thereof, a movable jaw opposing said stationary jaw on said one side surface thereof and including a gripping tang at one end thereof that is directed toward said protuberance and a handle portion at the other end thereof, with said movable jaw being pivoted to said fixed jaw for pivotal movement of said tang toward and away from said fixed jaw about an axis intermediate said ends of said movable jaw, and means for biasing said tang toward said fixed jaw, the improvement wherein:

said protuberance at its mid portion is formed to define an opening therethrough having a burr formed thereabout and projecting toward said movable jaw, said movable jaw being mounted to dispose said tang thereof insubstantial centered'relation with said protuberance burr and spaced therefrom but less than the thickness of the film in the closed position thereof against the film, said tang having a blunt gripping edge portion that engages the film under said biasing means to press the film against said burr.

5. The improvement set forth in claim 4 wherein:

said fixed jaw defines stop surfaces on either side of said protuberance and spaced therefrom,

said movable jaw defining on either side thereof tab portions positioned to receive the film between same and the respective stop surfaces respectively,

said stop surfaces being in the path of movement of the respective tab portions,

said stop surfaces and said burr being in substantial coplanar relation and said stop surfaces being disposed intermediate said axis and said protuberance opening,

whereby a dental film applied over said protuberance and said stop surfaces and under said tang and said tab portions is gripped at said stop surfaces by said tab portions and by said tang edge portion pressing same against said burr.

6. The improvement set forth in claim 5 wherein:

said tang edge portion is generally rectilinear in configuration,

said tang edge, said opening, and said burr being disposed in planes paralleling said fixed jaw end portion.

7. The improvement set forth in claim 6 wherein:

said tang edge portion has a length approximating one-half the width of said opening. 

1. In a film processing hanger including a film clip comprising a stationary jaw, and a movable jaw mounted for movement toward and away from the fixed jaw, and means for biasing the movable jaw toward the fixed jaw, the improvement wherein: said fixed jaw includes a substantially flat gripping portion having a protuberance formed therein directed toward said movable jaw, said protuberance at its mid portion being formed to define an opening therethrough having a burr formed thereabout and projecting toward said movable jaw, said movable jaw defining a tang formed with a blunt gripping end and said tang being mounted relative to said fixed jaw such that in the closed position thereof said movable jaw tang end is substantially centered on and spaced from said protuberance opening, whereby the film is pressed against said burr by said tang gripping end without said tang end penetrating the film.
 2. In a film processing hanger including a film clip comprising a stationary jaw having a generally planar gripping end including a generally spherically contoured protuberance on one side surface thereof, a movable jaw opposing said stationary jaw and including a gripping end directed toward said protuberance, and means for biasing said movable jaw end toward said protuberance, the improvement wherein: said protuberance at its mid portion is formed with a circular burr projecting substantially normally of said one surface and in the general direction of said movable jaw end, said movable jaw being mounted to dispose said end thereof in substantial centered relation with said protuberance burr and spaced therefrom but less than the thickness of the film in the closed position thereof.
 3. In a film processing hanger including a film clip comprising a fixed jaw having a gripping end portion defining a generally planar gripping section including a generally spherical protuberance on one side surface thereof, a movable jaw opposing said fixed jaw and including a gripping tang at one end thereof that is directed toward said protuberance, and a handle portion at the other end thereof, with said movable jaw being mounted for pivotal movement of said tang toward and away from said fixed jaw about an axis intermediate said ends thereof, and means for biasing said movable jaw tang toward said fixed jaw, the improvement wherein: Said protuberance at its mid portion is formed with a circular burr projecting substantially normally of said one surface and in the general direction of said movable jaw said one end, said movable jaw being mounted to dispose said tang thereof in substantial centered relation with said protuberance burr in the closed position thereof, and stop means for spacing said tang from said protuberance but less than the thickness of the film in the closed position thereof, said tang having a blunt gripping end portion that engages the film to press same against said protuberance burr in said closed position of said tang.
 4. In a dental film processing hanger for holding both acetate and polyester dental film including a film clip for holding the film and comprising a fixed jaw secured to the hanger and defining a gripping end portion projecting from the hanger and terminating in a marginal edge, said fixed jaw end portion being formed to define a generally planar gripping section including a spherically contoured protuberance on one side surface thereof, a movable jaw opposing said stationary jaw on said one side surface thereof and including a gripping tang at one end thereof that is directed toward said protuberance and a handle portion at the other end thereof, with said movable jaw being pivoted to said fixed jaw for pivotal movement of said tang toward and away from said fixed jaw about an axis intermediate said ends of said movable jaw, and means for biasing said tang toward said fixed jaw, the improvement wherein: said protuberance at its mid portion is formed to define an opening therethrough having a burr formed thereabout and projecting toward said movable jaw, said movable jaw being mounted to dispose said tang thereof in substantial centered relation with said protuberance burr and spaced therefrom but less than the thickness of the film in the closed position thereof against the film, said tang having a blunt gripping edge portion that engages the film under said biasing means to press the film against said burr.
 5. The improvement set forth in claim 4 wherein: said fixed jaw defines stop surfaces on either side of said protuberance and spaced therefrom, said movable jaw defining on either side thereof tab portions positioned to receive the film between same and the respective stop surfaces respectively, said stop surfaces being in the path of movement of the respective tab portions, said stop surfaces and said burr being in substantial coplanar relation and said stop surfaces being disposed intermediate said axis and said protuberance opening, whereby a dental film applied over said protuberance and said stop surfaces and under said tang and said tab portions is gripped at said stop surfaces by said tab portions and by said tang edge portion pressing same against said burr.
 6. The improvement set forth in claim 5 wherein: said tang edge portion is generally rectilinear in configuration, said tang edge, said opening, and said burr being disposed in planes paralleling said fixed jaw end portion.
 7. The improvement set forth in claim 6 wherein: said tang edge portion has a length approximating one-half the width of said opening. 